He defended the national anthem singer for Games 3 and 4, 11-year-old Sebastien de la Cruz, the subject of negative comments on Twitter questioning his nationality and presuming that he is in the U.S. illegally. De la Cruz is an American citizen, a Spurs fan born and raised in San Antonio.

"Well, I would like to say that I would be shocked or surprised by the comments," Popovich said Thursday. "But given the fact that there's still a significant element of bigotry and racism in our nation, I'm not surprised. It still plagues us, obviously. And what I was surprised by was how proud these idiots were of their ignorance, by printing their names next to their comments."

Popovich was referring to some Twitter outbursts after De la Cruz's Game 3 appearance.

One comment from @uncled37, whose account was no longer in existence Thursday, said, "9 out of 10 chance that kid singing national anthem is illegal."

Another comment from an account taken down, @d_white26, said, "There's a little Mexican kid singing the National anthem...what has the world come too."

"He's a class act. Way more mature than most his age," Popovich said. "And as much as those comments by the idiots saddens you about your country, he makes you feel that the future could be very bright."